Artificial (~(137)Cs) and natural (~(40)K) radioactivity and total potassium in medicinal fungi from Yunnan in China

摘要

Evaluated has been radioactive contamination with Cs-137 in parallel to occurrence of K-40 and total K in 31 species of medicinal mushrooms from Yunnan, China. We chose species that were not previously studied. The activity concentrations of Cs-137 in the medicinal fungi in this study were low. The maximum values were 54 +/- 4 Bq kg(-1) dry biomass (db) in caps and 48 +/- 5 Bq kg(-1) db in stipes of saprotrophic fungus Gerronema xanthophyllum from the family of Tricholomataceae. Mushrooms with relatively higher activity concentrations of K-40 were among the non-polypore species but certain species from the genus Ganoderma such as G. applanatum, G. capense, G. philippii and G. sinense showed K-40 in the higher range of 900 +/- 240 to 1400 +/- 340 Bq kg(-1) db. The concentrations of total K in the fungal materials in this study were in the range from 2.9 +/- 6.5 g kg(-1) db in Fomes rufolaccatus to 110 +/- 6 g kg(-1) db in G. xanthophyllum. The species studied, which represented both some popular wood-decaying polypore fungi but also terrestrial forms from the herbal medicine of China, can be considered as little contaminated with Cs-137 and potentially good source of leachable K in extract and decoction or as a powdered form in capsules.